You guys are still missing my point that it’s not a TUI because non-text elements have been drawn to the frame buffer. This is actually a lot easier to do in DOS than it is in UNIX too by virtue of the fact that DOSs text mode isn’t a pseudo-teletype. In fact this is a trick I used to do all the time when writing software back in the 80s: draw a UI then fallback to printing characters for UI updates.
For that tracker to be a proper TUI it would have to use text characters for all of the UI elements, bevels included. You simply couldn’t do those 3-tone bevels with any alt character sets, let alone an 8-bit one from the era of DOS.
What frame buffer? There is no frame buffer. It runs in text mode, thus it's a TUI. Would you consider Norton's text-mode interfaces not TUIs because they would redefine some characters for window chrome and a mouse pointer?
Are you sure? It seems to me that they were probably replacing some text characters with their own sprites instead. They could still be text characters, just redefined for their purposes.
For that tracker to be a proper TUI it would have to use text characters for all of the UI elements, bevels included. You simply couldn’t do those 3-tone bevels with any alt character sets, let alone an 8-bit one from the era of DOS.